Key-responsive calculating machine



July 31, 1956 c. F. WEBB 2,756,932

KEY-RESPONSIVE CALCULATING MACHINE Filed Dec. 22, 1951 2 Sheets-Sheet 1 INVENTOR. CHRISTOPHER FREDERICK WEBB ATTORNEYS C. F. WEBB July 31, 1956.

KEY-RESPONSIVE CALCULATING MACHINE 2 Sheets-Sheet 2 Filed Dec. 22, 1951 INVENTOR. CHRISTOPHER FREDERICK WEBB /ZW i ATTORNEYS United States Patent 2,756,932 KEY-RESPONSIVE CALCULATING MACHINE Christopher Frederick Webb, London, England, assignor to Bell Punch Company Limited, London, England, a British company Application December 22, 1951, Serial No. 262,952 Claims priority, application Great Britain January 5, 1951 8 Claims. (Cl. 235-62) This invention relates to a calculating mechanism for the four processes of arithmetic in Which the answers are displayed as numerals, and has for its object the provision of a manually key-controlled, but preferably power driven, machine in which the speed and efiiciency is increased and the mechanism simplified.

In accordance with the present invention, there is provided a calculating machine having a plurality of orders in which, upon the depression of a key of any of the orders, a mechanism associated with that order, hereinafter re ferred to as the line mechanism, is initially moved under the tension of a spring into a position related to the key which has been depressed and is arrested in that position by the engagement of a stop bar with the stem of the depressed key. A mass is provided which is moved under the tension of the spring referred to with the line mechanism until motion of the line mechanism is arrested by the stop bar whereupon, due to the momentum of the mass, the mass continues to move and, in so doing, brings the line mechanism into operative engagement with the power driving means of the machine.

The inertia of the mass is also utilized to actuate a trip mechanism releasing a rack which has been positioned by the displacement of the stop bar, permitting the rack to move into engagement with the pinion of the numeral wheel of the corresponding order which is to be actuated to a degree determined by the key depressed.

There is also included a key bar which is displaced upon the actuation of a key and serves to initiate the operation of the machine and to retain the depressed key in a depressed condition until the stop bar engages the depressed key stem. The trip mechanism referred to above serves also to isolate the key bar from the line mechanism at the time the trip mechanism is actuated, permitting the depressed key to return to its normal position before the completion of the actuation of the numeral wheel by the line mechanism and the rack gear.

The invention will be more particularly described with reference to the accompanying drawings, in which:

Figure 1 illustrates a preferred embodiment of the present invention which is applicable to both manually and power operated machines, and

Figure 2 illustrates a modification of the arrangement illustrated in Figure 1 which is preferably applicable to power operated machines.

Each of the two methods of carrying the invention into effect illustrated in the accompanying drawings comprises a machine of the multiple bank type having a series of rows of keys, one for each order. It is believed that a description of a single order of each embodiment will suffice for a full appreciation of the present invention as applied to a complete machine.

In the preferred embodiment illustrated in Figure 1 a numeral wheel 1 is given an angular displacement, which varies according to the digital value of the acuated key, by means of a reciprocating quadrant rack 2, which is normally held out of engagement with a pinion 3 connected to the numeral wheel 1, and moves to its keyselected position before being permitted to engage with the pinion 3 for registration during the return stroke. The registering mechanism of both embodiments of the present invention hereinafter described, conforms substantially to registering mechanisms well known in the art and such as those disclosed in my United States Patents No. 2,291,853, dated August 4, 1942, and No. 2,356,714, dated August 22, 1944, and, therefore, will not be specifically described.

A single order of the machine comprises a series of plates spaced apart by tubes having rods or bolts extending centrally therethrough, and transversely through the machine to form a complete framework. Various other stationary transordinal shafts or rods also extend through the machine.

A 3-armed lever 4 and a V-shaped lever 5 are pivoted respectively on rods 6 and 7 mounted in the machine frame and are freely coupled together by a momentum rod 8. The S-armed lever 4 is pivoted at its forward end to a link 9 which is pivoted to the crank arm 10 between one end of the crank arm which is pivoted to the machine frame and the other end, which in turn is connected to one end of a second link 11. The other end of the link 11 is pivoted to the quadrant rack 2. The quadrant rack 2 is freely connected to a downwardly extending limb 12 of a bell-crank lever 13 arranged to pivot about a fixed axis 14 and having a horizontal rearwardly extending leg 15 which terminates in a toepiece 16.

One end of a spring 17 is connected to the 3-armed lever 4 so as to tend to move, through the medium of the momentum rod 8 both the 3-armed lever 4 and the V-shaped lever 5 in a clockwise direction. The other end of the sprin 17 is connected to the downwardly extending limb 12 of the bell-crank lever 13, and tends to move the lever 13 in a clockwise direction, but when the mechanism is at rest such movement is prevented by a downwardly extending lug 19a on the inertia bar 8, obstructing the path of a lateral lug formed on the downwardly extending limb 12 of the lever 13.

One end of the momentum rod 8 is pivotally connected at 18 to the V-shaped member 5. The other end of the momentum rod 8 is slidably mounted on a pin 50 mounted on a stop bar 19 so as to permit longitudinal relative movement between the momentum rod 8 and the stop bar 19. The momentum rod 8 is pivoted at 51 to an arm of the 3-armed lever 4. At a point along the length of the momentum rod 8 the stop bar 19 is pivotally connected to the momentum rod 8 by a link 20, having a downwardly extending lug 21. Arranged to extend between the lug 21 and a corresponding lug 22 formed on the momentum rod 8 is a spring 23.

The levers 4 and 5 are normally restrained from moving by a locking roller 24 carried upon the rear arm of the V-shaped lever 5, bearing upon a horizontal surface 25 formed on a pivoted latch member 26.

In this condition the toe-piece 16 on the bell-crank lever 13 is arranged so as to be just clear of a shoulder 27 formed on a trip lever 28 for the reason hereinafter set forth.

A series of digit keys 29 are guided at each end in flanges formed on the frame, and are normally retained in a raised position. Each key is provided with a projecting lug 30 so arranged that upon depression of a key, it displaces a key-bar 31 in a longitudinal direction, whilst at the same time it brings portions 31a of the keybar 31 opposite the lugs on the other keys, and prevents the downward movement thereof. The key-bar 31 is pivotally mounted at the rear end thereof at 52 to one end of a rocking-stirrup 32 and is slidably mounted upon a pin 32a at the forward end thereof. The other end of the rocking-stirrup 32 is mounted on a fixed pivot 53. Pivotally mounted about the pivot 52 with key-bar 31 and the rocking stirrup 32 is a drag-pawl 33 which is provided at its rear end with a hook 34 which, when pulled towards the front of the machine by a forward movement of the key-bar 31, engages with a hook 54 extending from a release member 35 which is adapted to pivot about the same axis 36 as the latch member 26. The latch member 26 is provided with a lug 34a positioned in a step formed in the drag pawl 33 and to the left of the hook 54 as viewed in Figure 1. Thus, upon movement of the drag pawl 33 toward the front of the machine, both the release member 35 and the latch member 26 swing about their pivotal axis 36 towards the front of the machine, thus releasing the locking roller 24 on the V-shaped lever 5.

During forward movement of the V-shaped lever 5, both the momentum rod 8 and the stop bar 19 move together, but when the forward movement of the stop bar 19 is arrested, at any one of the predetermined number of key positions by the stem of the depressed key 29 engaging with the corresponding abutment 37 of the stop bar 19, the momentum rod 8 together with the levers 4 and continue by momentum to move forwardly and, in so doing, effect the release of the trip-lever 28. The triplever 28 is of stirrup construction, having a horizontally disposed arm 38 thereof projecting forwardly. The upper edge of the horizontal arm 38 is of arcuate formation, the radius of the are being approximately the distance of the upper edge from the stop bar 19. Extending from the stop bar 19 is an arm 39. The lower edge of the arm 39 moves adjacent to the upper edge of the horizontal arm 38 as long as the stop bar 19 is moving, but when motion of the stop bar 19 is arrested, and with it the pivotal axis 55' of the link 20 joining the stop bar 19 with the momentum rod 8, the momentum rod swings forwardly and the link 20 moves the stop bar 19 downwardly against the influence of the spring 23 to move the trip-lever 28 about its pivot 40, thus permitting the spring 17 connected to the lower arm 12 of the bellcrank lever 13 to pull the selected tooth of the rack 2 into engagement with the pinion 3 of the numeral wheel 1.

Upon the displacement of the trip-lever 28 which enables the toe-piece 16 of the bell crank lever 13 to descend to move the rack 2 into mesh with the pinion 3, the toe-piece 16 immediately pushes down a pawl 41 which is pivotally mounted on the drag-pawl 33 and yieldingly connected by means of a spring 42 to the latch member 26. During the forward movement of the keybar 31 the pawl 41 is carried under the toe-piece 16. The depression of the pawl 41 lifts the rear end of the drag pawl 33, thus holding the drag pawl 33 clear of the lug 54 and the lug 34a releasing the release member 35 and the latch member 26. The arrangement is such as to prevent the key bar 31 and the depressed key 29 from returning to at rest positions when the roller 24 mounted on the V-shaped lever 5 is behind the arcuate surface of the latch member 26 and before the depression of pawl 41 lifts the rear end of the pawl 33 clear of the lug 54. This ensures that a key once depressed cannot rise until the stop bar 19 has reached it, and this has been followed by the lifting of the drag pawl 33 as described above.

The object of the above sequence of operations, is to disconnect the key-bar 31 and, therefore, key 29, as soon as effective movement of the quadrant rack 2 towards the pinion 3 has commenced, at which stage in the cycle of operations the key 29 is no longer required, and is thus freed for return at the earliest possible moment in readiness for further operation, and in fact the next depression of the key can be made while the previous It will be observed that amount is being registered. the pawl 41 is pivoted to the drag-pawl 33, and therefore in addition to pulling down the forward end of the dragpawl the tooth of the pawl can yield against the influence of the spring 42 rearwardly if required. This condition can arise in fast repetition if a key is re-depressed before the registering cycle is complete, whereby the key-bar 31 and the drag-pawl 33 are again moved forwardly before the toe-piece 16 has restored. In such circumstances the latch member 26 has again been moved forwardly out of the path of the roller 24 mounted on the V-shaped lever 5, and as soon as the toe-piece 16 has moved past the pawl 41, and a driving pawl 43 (hereinafter described) has become disengaged, a further operating cycle will commence automatically.

Immediately following the depression of the pawl 41 pivoted on the drag-pawl 33, and toward the end of the engagement of the quadrant rack 2 with the pinion 3 of the numeral wheel 1, the descending toe-piece 16 also depresses the driving-pawl 43 which is pivotally mounted at 43a on the V-shaped lever 5, and is normally maintained by a spring clear of the teeth of a power-driven ratchet wheel 44.

During the selection movement of the V-shaped lever 5, hereinbefore described, the driving-pawl 43 travels in a substantially horizontal forward direction, and immediately following the preceding operations, that is, coincident with the full engagement of the quadrant rack 2 with the pinion 3 of the numeral wheel 1, the drivingpawl 43 is depressed by the toe-piece 16 to bring the abutment 45a into engagement with a tooth of the rotating power-driven ratchet wheel 44, whereby the whole line mechanism is returned rearwardly to its normal position of rest, with consequent registration on the numeral wheel.

The shape of the teeth of the ratchet wheel, the plane of the inclined surface 45 adjacent to the abutment 45a and the position of the abutment 45a on the surface 45 are such that during this return movement the driving pawl 43 is drawn downwardly to maintain engagement with the power-driven ratchet wheel 44, until the forwardly inclined surface 45 of the driving-pawl 43 is lifted by the next following tooth on the power-driven ratchet wheel 44, and that at the moment the driving-tooth of the power-driven ratchet wheel 44 disengages the drivingpawl 43, the tooth of the power-driven ratchet wheel 44 is substantially on a line joining the centre of the powerdriven ratchet wheel 44 with the pivotal axis 43a of the driving-pawl 43. In these circumstances, the velocity imparted to the mechanism decelerates toward the end of the registration stroke, and approximates zero at the moment the driving-pawl 43 is moved out of engagement with the power-driven ratchet wheel 44. Immediately upon release, the driving-pawl 43 is drawn clear by the spring thereof, and at the same time the shoulder on the latch-lever 26 passes under the roller 24 mounted on the V-shaped lever 5 until it is again released. Towards the end of the cycle the depending lug 19a on the momentum rod 8 again engages the depending arm 12 of the bellcrank lever 15 to withdraw the quadrant rack 2 from the pinion 3 of the numeral wheel 1, and permit the triplever 28 to restore to normal.

In the embodiment illustrated in Figure 2 a numeral wheel 1 is given an angular displacement, which varies according to the digital value of the actuated key, by means of a reciprocating quadrant rack 2, which is normally held out of engagement with a pinion 3 connected to the numeral wheel 1, and moves to its key-selected position before being permitted to engage with the pinion 3 for registration during the return stroke.

A 3-armed lever 4 and a V-shaped lever 5 are pivoted respectively on fixed rods 6 and 7. A stop bar 19 is pivoted at 50 to one arm of the 3-armed lever 4 and at 18' to the V-shaped lever 5, The 3-armed lever 4 is pivoted at its forward end to a link 9 which is connected to a crank arm 10, which in turn is connected to one end of a second link 11, the other end of which is pivoted to the quadrant rack 2. The quadrant rack 2 isfreely connected to a downwardly extending limb 12 of a bell-crank lever 13 arranged to pivot about a fixed axis 14 and having a horizontal rearwardly extending leg 15 which terminates in a toe-piece 16.

One end of a spring 17 is connected to the 3-armed lever 4 so as to tend to move, through the medium of the stop bar 19, both the 3-armed lever 4 and the V-shaped lever in a clockwise direction. The other end of the spring 17 is connected to the downwardly extending limb 12 of the bell-crank lever 13, and tends to move the lever 13 in a clockwise direction, but when the mechanism is at rest such movement is prevented by a downwardly extending lug 1% on the stop bar 1?, obstructing the path of a lateral lug formed on the downwardly extending limb 12 of the lever 13.

The levers 4 and 5 are normally restrained from moving by a locking roller 24 carried upon the rear arm of the V-shaped lever 5, bearing upon a horizontal surface 25 formed on a pivoted latch member 26.

In this condition the toe-piece 16 on the bell-crank lever 13 is arranged so as to be just clear of a shoulder 27 formed on a trip lever 28 for the reason hereinafter set forth.

A series of digit keys are guided at each end in flanges formed on the frame, and are normally retained in a raised position. Each key is provided with a projecting lug so arranged that upon depression of a key, it displaces a keybar 31 in a longitudinal direction, whilst at the same time, it brings portions 31a of the key-bar 31 opposite the lugs on the other keys, and prevents the downward movement thereof. The key-bar 31 is pivotally mounted at the rear end thereof at 52 to one end of a rocking-stirrup 32 and is slidably mounted at the forward end thereof upon a pin 32a. The other end of the rocking stirrup 32 is mounted on a fixed pivot 53. Pivotally mounted about the pivot 52 with the key-bar 31 and the rocking stirrup 32 is a drag-pawl 33 which is provided at its rear end with a hook 34 which, when pulled towards the front of the machine by a forward movement of the key-bar 31, engages with a lug 54 extending from a release member 35 which is adapted to pivot about the same axis 36 as the latch member 26. The latch member 26 is provided with a lug 34a positioned in a step formed in the drag pawl 33 and to the left of the hook 54 as viewed in Figure 2. Thus, upon movement of the drag pawl 33 toward the front of the machine, both the release member 35 and the latch member 26, swing about their pivotal axis 36 towards the front of the machine, thus releasing the locking roller 24 on the V-shaped lever 5.

During forward movement of the V-shaped lever 5, the stop bar 19 moves forwardly, but when the forward movement of the stop bar 19 is arrested, at any one of the predetermined number of key positions by the stem of the depressed key 29 engaging with the corresponding abutment 37 of the stop bar 19, a momentum weight 8' pivotally mounted on the lever 5 continues by momentum to move forwardly and, in so doing, effects the release of the trip-lever 28. The trip-lever 28 is of stirrup construction, enabling a horizontally disposed arm 38 thereof to project rearwardly. The under edge of the horizontal arm 33 is of arcuate formation, the radius of the are being the distance of the pivotal axis 20 of the momentum weight 8' from the lower edge 22' of the said weight. The lower edge of the momentum weight 8' moves adjacent to the lower edge 23' of the horizontal arm 38 as long as the stop bar 13 is moving, but when the stop bar 19 is arrested, the momentum weight 8 swings upwardly and moves the trip-lever 28 about its pivot 40, thus permitting the spring 17 connected to the lower arm 12 of the bell-crank lever 13 to pull the selected tooth of the rack 2 into engagement with the pinion 3 of the numeral wheel 1.

Upon the displacement of the trip-lever 26- which enables the toe-piece 16 of the bell crank lever 13 to descend to move the rack 2, into mesh with the pinion 3, the toepiece 16 immediately pushes down a pawl 41 which is pivofally mounted on the drag-pawl 33 and yieldingly connected by means of a spring 42 to the latch member 26. During the forward movement of the key-bar 31 the pawl 41 is carried under the toe-piece 16. The depression of the pawl 41 lifts the rear end of the drag pawl 33, thus holding the drag pawl 33 clear of the lug 54 and the lug 34a releasing the release member 35 and the latch member 26. The arrangement is such as to prevent the key bar 31 and the depressed key 29 from returning to at rest positions when the roller 24 mounted on the V-shaped lever 5 is behind the arcuate surface of the latch member 26 and before the depression of pawl 41 lifts the rear end of the pawl 33 clear of the lug 54. This ensures that a key once depressed cannot rise until the stop bar 19 has reached it, and thus has been followed by the lifting of the drag pawl 33 as described above.

The object of the above sequence of operations is to disconnect the key-bar 31 and, therefore, key 29, as soon as effective movement of the quadrant rack 2 towards the pinion 3 has commenced, at which stage in the cycle of operations the key 29 is no longer required, and is thus freed for return at the earliest possible moment in readiness for further operation, and in fact the next depression of the key can be made while the previous amount is being registered. It will be observed that the pawl 41 is pivoted to the drag-pawl 33, and therefore in addition to pulling down the forward end of the drag-pawl the tooth of the pawl can yield rearwardly if required against the influence of the spring 42. This condition can arise in fast repetition if a key is re-depressed before the registering cycle is complete, whereby the key-bar 31 and the drag-pawl 33 are again moved forwardly before the toe-piece 16 has restored. In such circumstances the latch member 26 has again been moved forwardly out of the path of the roller 24 mounted on the V-shaped lever 5, and as soon as the toe-piece 16 has moved past the pawl 41, and a driving pawl 43 (hereinafter described) has become disengaged, a further operating cycle will commence automatically.

Immediately following the depression of the pawl 41 pivoted on the drag-pawl 33, and towards the end of the engagement of the quadrant rack 2 with the pinion 3 of the numeral wheel 1, the descending toe-piece 16 also depresses the driving-pawl 43 which is pivotally mounted on the V-shaped lever 5, and is normally maintained by a spring clear of the teeth of a ratchet wheel 44 driven by a motor 47.

During the selection movement of the V-shaped lever 5, hereinbefore described, the driving-pawl 43 travels in a substantially horizontal forward direction, and immediately following the preceding operations, that is, coincident with the full engagement of the quadrant rack 2 with the pinion 3 of the numeral wheel 1, the drivingpawl 43 is depressed by the toe-piece 16 to bring the abutment 45a into engagement with a tooth of the rotating power-driven ratchet wheel 44, whereby the whole line mechanism is returned rearwardly to its normal position of rest, with consequent registration on the numeral wheel.

The shape of the teeth of the ratchet wheel, the plane of the inclined surface 45 adjacent to the abutment 45a and the position of the abutment on the surface 45 are such that during this return movement the driving-pawl 43 is drawn downwardly to maintain engagement with the power-driven ratchet Wheel 44, until the forwardly inclined surface 45 of the driving-pawl 43 is lifted by the next following tooth on the power-driven ratchet wheel 44, and that at the moment the driving-tooth of the powerdriven ratchet wheel 44 disengages the driving-pawl 43, the tooth of the power-driven ratchet wheel 44 is substantially on a line joining the centre of the power-driven ratchet wheel 44 with the pivotal axis 43a of the drivingpawl 43. In these circumstances, the velocity imparted to the mechanism decelerates towards the end of the registration stroke, and approximates zero at the moment the driving-pawl 43 is moved out of engagement with the power-driven ratchet wheel 44. Immediately upon release, the driving-pawl 43 is drawn clear by the spring thereof, and at the same time the shoulder on the latchlever 26 passes under the roller 24 mounted on the V- shaped lever until it is again released. Towards the end of the cycle the depending lug 19a on the stop bar 19 again engages the depending arm 12 of the bell-crank lever 13 to withdraw the quadrant rack 2 from the pinion 3 of the numeral wheel 1, and permit the trip-lever 28 to restore to normal.

The sequence of five automatic functions which is efiected in both embodiments may be summarized as follows:

1. The forward secondary movement of the momentum bar or the depending weight is effected by momentum after the stop bar of the line mechanism has been arrested.

2. The trip-lever is released as a result of the secondary movement of the momentum bar or the depending weight.

3. The toe-piece of the bell-crank descends to initiate the engagement of the quadrant rack with the pinion of the numeral wheel.

4. The pawl mounted on the drag-pawl is depressed by the toe-piece, and the hook of the drag-pawl is raised by the said pawl to isolate the key-bar mechanism, and

5. The completion of the movement of the quadrant rack into engagement with the pinion of the numeral wheel and the final movement of the toe-piece to place the driving-pawl in driving engagement with power-driven ratchet wheel whereby registration is effected.

The above sets forth the general operation of each order of the machine, and presupposes the power rotation of a series of power-driven ratchet wheels, one for each order, fixed to a shaft and rotated by a motor through a train of gears. The motor may be arranged to rotate continuously or, to be switched into use by a contact indicated at 48 and operated by a common transverse bar 49 immediately any key-bar moves forwardly by the depression of a key. Means are also provided for cancelling the figures in the register by means of a common bar 60 adapted to lift all the detent pawls 61 in a manner shown in the Webb Patent 2,291,853 and is well known in the art.

Thus it will be seen that according to the present invention there is provided a calculating machine, in which means are provided for isolating the key-bar mechanism from the line mechanism in a simple and very etficient manner. The same means may, in addition, be employed in a calculating machine of the type in which a rack is moved in one direction whilst out of engagement with the pinion of the numeral wheel and, thereafter, moved into engagement with the said pinion and in the reverse direction to efiect registration, for the purpose of permitting the rack to be moved into engagement with the pinion of the numeral wheel when the forward movement of the stop-bar is arrested.

What is claimed is:

1. In a calculating machine an accumulator, depressible keys, means for actuating said accumulator in response to depression of a key, said actuating means including a first movable member, a second movable member movable relative to said first movable member and means for moving said movable members upon actuation of said actuating means, means for arresting the movement of said first movable member during operation of said actuating means, means for driving said actuating means and for restoring said movable members to their initial positions, and means actuated by relative movement between said two members when movement of said first member is arrested resulting from the inertia of said second member for actuating said driving means.

2. In a calculating machine an accumulator, depressible keys, means for actuating said accumulator in response. to

depression of a key, said actuating means including a first movable member, a second movable member movable relative to said first movable member and means for moving said movable members upon actuation of said actuating means, means including the stem of the depressed key for arresting the movement of said first movable member during operation of said actuating means, rotating means for driving said actuating means and for restoring said movable members to their initial positions, and means including a clutch actuated by relative movement between said two members when movement of said first member is arrested resulting from the inertia of said second member for connecting said driving means in driving relation with said actuating means.

3. in a calculating machine an accumulator, depressible keys, means for actuating said accumulator, said actuating means including a first movable member and a second movable member movable relative to said first member, means for moving said movable members upon actuation of said actuating means, means displaced by depression of a key for initiating the operation of said actuating means, means for locking said displaced means in its displaced position, means for arresting the movement of said first movable member during operation of said actuating means, means for driving said actuating means and for restoring said movable members to their initial positions, and means actuated by relative movement between said two members when movement of said first member is arrested resulting from the inertia of said second member for actuating said driving means and for releasing said displaced means from said displaced position before the completion of the cycle of operation of the actuating means.

4. In a calculating machine an accumulator, depressible keys, means for actuating said accumulator, said actuating means including a first movable member and a second movable member movable relative to said first member, means for moving said movable members upon actuation of said actuating means, means displaced by depression of a key for initiating the operation of said actuating means, means for locking said displaced means in its displaced position, means including the stem of the depressed key for arresting the movement of said first movable member during operation of said actuating means, rotating means for driving said actuating means and for restoring said movable members to their initial positions, and means including a clutch actuated by relative movement between said two members when movement of said first member is arrested resulting from the inertia of said second member for releasing said displaced means from said displaced position before the completion of the cycle of operation of the actuating means and for connecting said driving means in driving relation with said actuating means.

5. In a calculating machine depressible keys, an accumulator including a pinion gear, means for actuating said accumulator in response to the depression of a key, said actuating means including a first movable member, a second movable member movable relative to said first movable member, a rack gear movable in response to movement of said first movable member and normally disengaged from said pinion, and means for moving said movable members upon actuation of said actuating means, means for arresting movement of said first movable member and said rack gear at predetermined positions during operation of said actuating means, and means actuated by relative movement between said two members when movement of said first member is arrested resulting from the inertia of said second member for moving said rack gear into engagement with said pinion gear.

6. In a calculating machine depressible keys, an accumulator including a pinion gear, means for actuating said accumulator in response to the depression of a key, said actuating means including a first movable member, a second movable member movable relative to said first movable member, a rack gear movable in response to movement of said first movable member and normally disengaged from said pinion, and means for moving said movable members upon actuation of said actuating means, means for arresting movement of said first movable member and said rack gear at predetermined positions during operation of said actuating means, means for driving said actuating means and for returning said movable members and said rack gear to their initial positions, and means actuated by relative movement between said two members when movement of said first member is arrested resulting from the inertia of said second member for actuating said driving means and for moving said rack gear into engagement with said pinion gear during the returning stroke of the rack gear.

7. In a calculating machine depressible keys, an accumulator including a pinion gear, means for actuating said accumulator in response to the depression of a key, said actuating means including a first movable member, a second movable member movable relative to said first movable member, a rack gear movable in response to movement of said first movable member and normally disengaged from said pinion, and means for moving said movable members upon actuation of said actuating means, means for arresting movement of said first movable member and said rack gear at predetermined positions during operation of said actuating means, rotating means for driving said actuating means and for returning said movable members and said rack gear to their initial positions, and means including a clutch actuated by relative movement between said two members when movement of said first member is arrested resulting from the inertia of said second member for connecting said driving means in driving relation with said actuating means and for moving said rack gear into engagement with said pinion gear during the returning stroke of the rack gear.

8. In a key responsive calculating machine having a keyboard comprising a plurality of orders of keys, an accumulator mechanism having a plurality of orders com prising an order for each order of keys, an actuator for each order of said accumulator mechanism, engaging means retaining each actuator in a position of rest, means operable upon the actuation of a key of an order to displace the actuator from the position of rest to a variable point determined by the digital value of the actuated key, rotating power means associated with each actuator, driving means operatively connected to each actuator, means for bringing said driving means into connection with said rotating power means at said variable point in the operative cycle of the actuator to move the actuator in the direction of the position of rest thereof, said connecting means cooperating with said power means to effect disconnection of the driving means from said power means at an invariable point in the operative cycle of the said actuator.

References Cited in the file of this patent UNITED STATES PATENTS 1,371,953 Turck Mar. 15, 1921 1,909,714 Pasinski May 16, 1933 2,063,962 Turck Dec. 15, 1936 2,240,797 Pasinski May 6, 1941 2,568,616 Gourdon Sept. 18, 1951 2,569,508 Webb Oct. 2, 1951 

